| 简介 |
Intersil公司的ISL78020和ISL78022是高性能汽车级TFT-LCD升压电源解决方案,它具有2个用于 VON 和VOFF的LDO控制器,一个有可调延时的VON边电路以及用于VCOM 和 VGAMMA的放大器,输出电压精度1%,效率大于90%,同时还集成了18V/3A 的FET,特别适合用在汽车电子的TFT-LCD显示器升压电源。本文介绍了ISL78020和ISL78022的主要性能,方框图,升压控制器方框图以及典型应用电路。 Intersil Automotive Grade TFT-LCD DC/DC with Integrated Amplifiers
The ISL78020 and ISL78022 integrate a high performance boost regulator with 2 LDO controllers for VON and VOFF, a VON-slice circuit with adjustable delay and either one (ISL78020) or five (ISL78022) amplifiers for VCOM and VGAMMA applications. The boost converter in the ISL78020 and ISL78022 is a current mode PWM type integrating an 18V N-Channel MOSFET. Operating at 1.2MHz, this boost converter can operate in either P-Mode for superior transient response, or in PI-Mode for tighter output regulation. Using external low-cost transistors, the LDO controllers provide tight regulation for VON, VOFF, as well as providing start-up sequence control and fault protection. The amplifiers are ideal for VCOM and VGAMMA applications, with 150mA peak output current drive, 12MHz bandwidth, and 12V/μs slew rate. All inputs and outputs are rail-to-rail. Available in a 32 Ld TQFP (7mmx7mm) Pb-free package, the ISL78020, ISL78022 are specified for operation over a -40°C to +105°C temperature range. 主要特性: Current mode boost regulator Fast transient response 1% accurate output voltage 18V/3A integrated FET >90% efficiency 2.6V to 5.5V VIN supply 2 LDO controllers for VON and VOFF 2% output regulation VON-slice circuit High speed amplifiers 150mA short-circuit output current 12V/μs slew rate 12MHz -3dB bandwidth Rail-to-rail inputs and outputs Built-in power sequencing Internal soft-start Multiple overload protection Thermal shutdown 32 Ld 7x7 TQFP package Pb-free (RoHS compliant)
应用: All automotive TFT-LCD panels

图1.ISL78020, ISL78022方框图

图2. ISL78020, ISL78022升压控制器方框图

图3.典型应用电路图
来源:中电网 |